1. Field of the Invention
This invention relates to a surgical clip for closing an incision in body tissue and more particularly to a fascia clip of two piece construction comprising a staple and a retainer and an instrument for applying the staple.
2. Description of the Related Art
Surgical fasteners have been used in surgical procedures to eliminate the need for suturing, which is both time consuming and inconvenient. In these applications the surgeon can use a fastener implanting device loaded with one or more surgical fasteners to accomplish in a few seconds what would have taken many minutes to perform by suturing. This reduction in operating time reduces blood loss and trauma to the patient.
In some applications, two part surgical fasteners are used in which the fastener is inserted at the wound site and is engaged by a retainer to hold the fastener in place. These retainers prevent the fastener from working loose from the tissue. Since the two piece fasteners cannot easily be unlocked and are not easily removable, they are made of bioabsorbable material.
Possible materials for such two part fasteners include polymers and copolymers of glycolic acid (i.e. hydroxyacetic acid), the cyclic dimer of glycolic acid ("glycolide"), lactic acid, the cyclic dimer of lactic acid ("lactide") and related monomers. Polymers and copolymers of the foregoing kind and absorbable surgical devices made therefrom are well known. See, e.g., U.S. Pat. Nos. 2,668,162; 2,703,316; 2,758,987; 3,225,766; 3,297,033; 3,422,181; 3,531,561; 3,565,869; 3,620,218; 3,626,948; 3,636,956; 3,736,646; 3,772,420; 3,773,919; 3,792,010; 3,797,499; 3,839,297; 3,867,190; 3,878,284; 3,982,543; 4,060,089; 4,137,921; 4,157,437; 4,234,775; 4,237,920; 4,300,565; and 4,523,591; U.K. Patent No. 779,291; D. K. Gilding et al., "Biodegradable polymers for use in surgery--polyglycolic/poly(lactic acid) homo- and co-polymers: 1, Polymer, Volume 20, pages 1459-1464 (1979), and D. F. Williams (ed.) Biocompatibility of Clinical Implant Materials, Vol. II, ch. 9: "Biodegradable Polymers" (1981).
The use of prior fasteners and instruments has not been entirely suitable for all types of tissue. For example, many of the prior fasteners are not suitable for closing fascia tissue incisions because the tissue is relatively thick and not easily manipulated. U.S. Pat. No. 4,950,284 discloses one type of clip suitable for fascia tissue. The clip comprises a longitudinal strap which extends through an opening in the proximal end of the base and emerges through an opening at the distal end of the base.
The need exists for an improved surgical clip which can be utilized for fascia tissue, and is easy to manufacture, easy to manipulate, can be applied with accuracy, and provides a secure closure of the incision. The need also exists for an instrument for applying such surgical clip.